1. Field of the Invention
The present invention relates to a solenoid valve in which a moving part moves by electromagnetic force to close a valve.
2. Description of the Related Art
Conventionally, a solenoid valve is arranged such that, when it is energized and electromagnetic force is generated, a moving part having on its tip a valve that moves by the electromagnetic force, and a stroke of the moving part causes the valve to abut a sealing part of a fluid passage, which interrupts a flow of fluid.
The conventional solenoid valve, however, produces an actuating sound (impact sound) caused by a collision between the valve and the sealing part in abutting the valve against the sealing part of the fluid passage. For instance, when the solenoid valve is installed in a vehicle, depending on where the valve is installed, an actuating sound can be transmitted inside a vehicle as a noise.
JP 2001-227671 A (paragraph numbers 0014 to 0036, FIG. 1) discloses a solenoid valve in which an air orifice is formed in a diaphragm to decrease a moving speed of a moving part via the air orifice, thereby reducing loudness of an actuating sound. Nonetheless, a mere decrease in the moving speed of the moving part bumps immediately against bounds to reduction in the actuating sound, and depending on where the valve is installed, an actuating sound can be transmitted inside the vehicle as a noise.
The conventional solenoid valve thus arranged as above involves a problem that when the valve abuts the sealing part of the fluid passage, an actuating sound is produced by a collision between the valve and the sealing part, and depending on where the valve is installed, the actuating sound can be transmitted inside a vehicle as a noise